Printed circuit boards are often vertically mounted in racks utilizing a pair of end plates affixed at opposed ends of the board so as to provide both support for the board and spacing for the electrical components mounted thereon. In addition, one of the end plates may also function as a multicontact electrical plug for connecting the board to external circuitry.
In many applications a tubular cover generally rectangular in cross-section, is used to provide both electrical shielding and mechanical protection for the board and its electrical components. Typically, the cover is formed from sheet aluminum which is then welded and ground, lap jointed and spot welded, or dovetailed and staked along its abutting seam. All of these operations substantially increase the cost of making the protective cover. Alternately, the cover may be cut from an extruded aluminum tube. However, this is a relatively expensive structure, compared to the cost of such covers formed from sheet aluminum.